A simple way to select several components at a time is by using the Select Rectangle tool.
Figure 1
Follow these steps:
Make sure you have chosen Expert user level.
On the toolbar above the 2D view, click the button with the blue, dashed square icon.
Move the mouse pointer to the drawing area. A small rectangle follows.
Place the rectangle near one of the components you wish to temporarily group together.
Click and hold the mouse button, and expand the rectangle over the components you wish to select.
When you release the mouse button, the rectangle disappears. The yellow snap points are now visible on all selected components together with purple squares surrounding the components.